This invention relates to an outboard motor for a marine propulsion system, and more particularly to a latch structure for releasably securing separate cowl sections of an outboard motor.
It is known to provide a pivotable hook-type latch assembly for releasably securing upper and lower cowl sections for an outboard motor. Such a latch assembly typically includes a pivotably mounted hook interconnected with a pivotable latch lever. These components are mounted to one of the cowl sections. The other cowl section is provided with a catch assembly, which typically includes a stationary hook-engaging member. By operation of the pivotable lever, the hook is movable between an engaging position in which it engages the hook-engaging member provided on the catch assembly for securing the cowl sections together, and a disengaging position in which the hook and the hook-engaging member are disengaged, for releasing the cowl sections.
The above-described latch construction is typically employed in connection with a cowl design incorporating top and bottom cowl sections. In such a design, a compressible resilient rubber seal is typically provided between the cowl sections for improving the water resistance of the cowl assembly. Stationary mating engagement means is provided for fixing the position of the cowl sections relative to each other at one end of the cowl assembly, typically the front. The pivotable latch assembly and its associated catch assembly are provided at the other end of the cowl assembly, typically the rear, for releasably securing the cowl sections together upon engagement thereof. The latch assembly is designed to compress the rubber seal provided between the cowl sections for improving the water resistance of the cowl assembly and for providing opposing forces on the hook and catch for ensuring that the hook and catch remain engaged.
It has been recognized that the hook may become disengaged with the catch under certain operating conditions, resulting in disengagement of the top and bottom cowl sections. For example, when the lower unit of the outboard motor strikes a stationary obstacle, such as a submerged log or rock, the entire outboard motor assembly is caused to pivot about its tilt axis. In such a situation, the bottom cowl section pushes upwardly, on the rubber seal, while the top cowl section simultaneously pushes downwardly on the rubber seal, due to its inertia. In such a situation, the rubber seal is compressed, and the hook moves upwardly out of engagement with the hook-engaging member of the catch assembly. The latch lever, due to its inertia, may then pivot about its pivot axis, thus moving the hook to its disengaging position. As the outboard motor continues to pivot about its tilt axis and strikes the stops which define the allowable tilting movement of the unit, the top cowl section may continue to move forwardly due to its inertia and come loose from the bottom cowl section.
The present invention is designed to eliminate the possibility that the cowl sections may become disengaged during operation. In accordance with the invention, a latch assembly for releasably securing first and second cowl sections together includes a catch mechanism connected to one of the cowl sections and a latch mechanism connected to the other of the cowl sections. The latch mechanism is movable between an engaging position in which the catch mechanism is engaged for securing the cowl sections together, and a disengaging position in which the latch mechanism and the catch mechanism are disengaged, for releasing the cowl sections. The latch mechanism is capable of movement, when in its engaging position, out of engagement with the catch mechanism so as to be movable toward its disengaging position. Retainer means is provided for engaging the latch mechanism during such movement thereof out of engagement with the catch mechanism when the latch mechanism is in its engaging position, so as to prevent the latch mechanism from moving to its engaging position. In one embodiment, the latch mechanism includes a pivotably mounted hook movable in a first direction toward its engaging position and in a second direction toward its disengaging position. The hook is capable of movement in a third direction, other than the first and second directions, caused by compression of the compressible seal provided between the first and second cowl sections. In a typical application, the third direction is typically upwardly or downwardly vertical. The retainer means comprises a detent means provided on the hook, and engagement means held stationary relative to the catch mechanism for engaging the detent means on the hook during movement of the hook in the third direction. Upon such engagement, rotation of the hook toward its disengaging position is prevented. In a preferred embodiment, the hook is provided with an indentation, and the catch mechanism includes a tab aligned with the hook indentation when the hook is in its engaging position. In this manner, vertical movement of the indentation caused by compression of the compressible seal causes engagement of the tab with the indentation provided on the hook. The tab and indentation are preferably arranged so as not to interfere with normal movement of the hook in the first and second directions for engaging and disengaging the hook-receiving member of the catch mechanism. Rotation of the hook is only prevented during vertical movement of the hook caused by compression of the compressible seal beyond that normally provided by the hook upon its engagement with the catch mechanism.